From: Bruce Fortnam <bfortnam@GlobalLocate.com> - 2006-05-25 18:18:11
> I know that the gumstix can be brought into some kind of sleep mode,
> but, more importantly - can it bootstrap itself back from there?
> (by say, a timer) (and how sleepy is this sleep mode? What is shut
> I have not been able to find info on this on gumstix.org/tikiwiki or
the mailinglist archive
In sleep mode, everything in the PXA255 is shut down except the RTC and
Pin states are maintained as described in the Processor Developer's
All peripherals should be shut down before entering sleep mode,
and the core VCC supply is shut down by the PXA when sleep mode is
The dominant current in sleep mode should be the self-refresh current of
2.5 mA x 2 chips =3D 5 mA max.
As far as I can tell, no one has implemented the code to wake up from
without doing a full reboot.
To wake up from sleep mode with an external signal, you need to toggle
one of GP[15:0].
Since none of these signals is available on the Hirose 60-pin, the only
way to wake up
a basix board is with the internal RTC.
This is something that should be changed in future boards.